AN1711 datasheet(34/40 Pages) STMICROELECTRONICS

Part #	AN1711

Description	SOFTWARE TECHNIQUES FOR COMPENSATING ST7 ADC ERRORS

PDF	40 Pages

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Manufacturer	STMICROELECTRONICS [STMicroelectronics]

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SOFTWARE TECHNIQUES FOR COMPENSATING ST7 ADC ERRORS

for calibration and this range will not be calibrated. Thus, we need 4 external voltage refer-

ences for calibration.

For example:- We can choose to calculate the offset error at 10LSB and take the 2nd point of

the line at 509LSB.

We can ignore the analog input range from 509LSB to 517LSB.

For second line we take the first point as 517LSB and second as 1013LSB.

Figure 23. Hardware setup for 2-zone calibration

Using the same software technique mentioned in Section 4.2.6 the actual value can be calcu-

lated from the converted value.

Comments

1. This technique enables you to able to get close to the ideal result.

2. It requires external resistors and uses four analog channels for calibration and hence, it is

costly.

3. Some current will flow from the external resistor network.

AIN0

VAIN

ADC

Microcontroller

\/\/\/\/\/\/

AIN1

VDDA

VSSA

AIN2

AIN3

AIN4

AN1711 Datasheet(PDF) 34 Page - STMicroelectronics